Pneumatic-despatch-tube apparatus.



E. J. LORING.

PNEUMATIC DESPATCH TUBE APPARATUS.

APPLICATION nuzu JULY 19,1916.

1 ,258,422. Patented Mar. 5 1918.

Wflzesses.

W4 Ernest JLarm Q? A PB? 1mm Attorney UNITED STATES PATIENT OFFICE ERNEST J. LUBING, O33 SOMERVILLE, MASSADHUSETTS, AS$IGNOR TO THE LAMSON COMPANY, 033 IBQETUZN, MASSACHU$ETTS, A CORPORATION OF NEW JERSEY.

INEUMATICJ-IIJEGPATGH-TUBE APPARATUS.

Application filed July 19, 1916.

It) all ZtT/LOHL it may concern:

lie it known that I, l lnnns'r J. Lonnie, e citizen of the United States, residing at tiolnerville, in the county of ltlithllesex end State of Massachusetts, have invented eertnin new and usetul Improvements in Pneumntic-lJespntch-Tuhe APPHPMLHS, of which the following is a. specification.

This invention relates to pneumatictlespatch tube apparatus and more particularly to whet ishnown as a pressure system.

tine oi. the i'n'incil'ml objects of my invention is to provide it novel menus for control ling the operating pressures in :1 plurality of: transit tubes of (lill'erent lengths whereby to insure an adequate effective pressure in each for the proper trzmsmission or carriers tlnn'ethrough. 7

Another object is to construct said pressure controlling means so as to rerlucc noise and vibration of the ep tierntus substantially to n minimum. 7

Still another oh ect is to so constitute the eppsrntus as to enable it to meet the exact" mg service conditions incident to such institutions as stock exchanges and the like.

These anti other objects of? my invention will he hcrcinsfttn' referred. to null the novel combinations of means and elements where by said objects may be attained will he more v particularly pointed out in the claims uppenrleti hereto. 7

In the accompanying (i "airings which form it part hereol and in which like rcfen once characters designate like parts through out the respective views, I have exemplified a preferred embodiment of the invention, but. as I am aware of various changes and modifications "which may be made herein without departing from the spirit of said invention, I desire to be limited only by the scope of the claims.

Referring to the drawings:

Figure 1. is a somewhat diagrammatic representation of :1 system constructed in tic-- cordt-lncewith the principles of the invention viewed in sitle elevation; certain parts being broken away or shown in section for purposes of illustration. i V V Fig; 2 is a plan viewof it part, of said system, showing the disposition of the site tions and of different, leugthsof transit tuliing connecting said stations;

Specification of Letters Lletcnt.

Patented Mar. 5, 1918.

semi no. 110,218.

front elevation of said "l ig. 6 is a front elevation oi n modification oi said controller, differently aperturecl from the first; and i l 7 is o section of the same taken on line VIE-Will of Fig. 6.

'ihe trensniis on tubes -1-2-3--*l, when the system intei'nilerl for use in, for'cxelu pie, n stock exchange, are preferably, although not necessarily, pressure tubes,-the compressed air for propelling the carriers 5 tlnnethrough being supplied. in this case from u drone (i into which the air is delivered from no blower or pump '1" through a supply pipe 8, the blower preferably being th iren by e n electric motor 9 or the like The air en'lerg'ing from the lruni passes througl'i a nipple or pipe seetion'fttl and thence through a 'con'lhinution ilow-silencing untl presetll'eo'eg'ulnting device consisting oi :1 retaining sleeve ll and n mllllti[)ltHlOZZlGfi pinto l2 hereinafter more fully described.

The preferably continuously flowing air then passes through no spacing nipple or pipe 13 wliiich separates the controllerfrom the (les 'imtching terminal lu-fl; there lacing; one of these nt each of the trading or clerk stations .ztli fl l) from which carriers may he tlespntcl'ietl, post the correspomling solves it, to u delivery desk.

At this latter, a. novel terminal arrange ment is employed to economize space and :lacilitntc the expeditious handling of the incoming carriers.

Carriers emerging from, for example, the first of a pair of tubes 1, pass around the de tlector 15, which may be inex 'iensivcly con structcd oi bent sheet metal the upper side pressurc-controlle' end silencer incoming or return tubes have not been shown, to avoid confusion. As applied to a stock exchange, my improved tube system is preferably of the pressure type, compressed air being delivered from a single supply, such as the extended reservoir drum 6, to a considerable number of tube lines of various lengths each of which, as shown, normally discharges at, for example, the central desk and each with a certain fined rate of flow. In some stock exchanges, it is re garded as desirable on certain service, to coordinate the various lines to the end that carriers may be transmitted between A and E, and between B and E, etc, with substantially an equal period of transmission from each of the brokers stations, since otherwise one broker would be unduly favored over another.

One plan for equalizing the time of trans- 7 mission would be to make all of the tubes of equal length; but this would not only involve useless Waste of tubing but even then the bonds or turns in some of the tubes would be apt to be sharper than the bends in others and again a slight but appreciable difference in the times of transmission would result.

Again, the pressure in the drum must be sufficient to properly transmit carriers through the longest line but for the shorter lines wherein the flow resistance is obviously less, if some provision be not made to throttle down the air flow there will of course be a tendency for the heaviest current of air to flow through the shortest line. In some cases it is desirable to produce equal rates of flow in all of the lines, but if the system is to be one such as that just mentioned, this cannot be permitted, but rather, the air flow through the longest tube should be the greatest. and the rate of flow through the shorter tubes correspondingly less, to effect the transmission of carriers through the various lines in equal times.

\Vhether equal rates of flow are desired or equal transmission times, therefore, some resistance affording means must be provided to control the outrush of air from the drum. I have attempted to provide for this resistance by means of sliding gates and butterfly vanes, but the surfaces of such gates are not favorably arranged for the quiet passage of air at the high velocities which necessarily accompany marked constrictions of the flow. 1 have, however, discovered that if the resistance is applied by means of a constricting nozzle or nozzles in the line of flow,the surfaces in contact with the highvelocity air, being fixed, may be arranged in accordance with the results of experiments which 1 have conducted, to aflord the degree of quietness of operation required.

For usual conditions where the pressure difference on the respective receiving and delivery ends of the nozzle is not great, or in otherwords where thisditference is materially less than the critical value 1 2 .31 3 ,48 for air)? i l have found that the most favorable form of nozzle aperture is a short straight throat or bore with an approach, the curves in which are on easy flow lines. For maximum quietness of operation it is important that the stream be well supported by the Walls of the nozzle'and any sudden constriction or over-cxpansion should beavoided. Indeed,

even a slight rounding of the flow-directing walls of the nozzle orifice at the discharge end of the latter is objectionable.

When air flows through a nozzle such as above described, if the axis of the nozzle orifice be substantially coincident with the axis of the tube in which said nozzle is disposed, a partial vacuum is formed adjacent the walls of the tube and just beyond the nozzle. and it is probably this vacuum which causes a turbulence ,offlow which creates a noise.

I have found that this effect may be counteracted by surrounding the central nozzle orifice by a ring of smaller apertures of the same type, as shown in Figs. 6 and 7 wherein the nozzleplate 12' has a relatively large central orifice 12 around which are located a number of secondary openings 12", similar in general contour but considerably smaller in diameter.

In Figs. 4 and 5 I have shown an equivalent nozzle-plate 12 which on account of its simpler shape is to bepreferred; the large central orifice being in this case replaced by a series of smaller ones 12 distributed with approximate uniformity over the partition or plate which I have termed in general a nozzle plate but which may perhaps be more aptly termed a multiple nozzle.

If such a series of nozzle apertures be grouped in a more compact unit at the center of the tube. the result approaches that afforded by a single relatively large nozzle momentarily or until it has again resumed its normal speed,-more vigorously toward its destination.

Second: the multiple-nozzled device has no movable or loose parts, such as a gate or vane, to rattle and constitute a source of objectionable noise; nor has it relatively sharp edges such as are commonly present in gates and valves and past which the air current would flow with a whistling or hissing sound.

Having thus described my invention what I claim is:

l. A pressure pneumatic tube system comprising a series of transit tubes through which carriers are propelled by compressed air, a despatching inlet for each of said tubes, a drum constituting a source of pres sure fluid for said tubes, connections between said inlets and said drum, and a combina tion silencing'derice and pressure-regulator for each of saideonnections for offering a predetermined resistance to the air flowing into the corresponding tube, the comparative resistance of each. device to the air flow passing the same being substantially inversely proportionate to the flow resistance of the tube corresponding to said device.

2. A pressure pneumatic tube system comprising a plurality of transit tubes'respectirely extending between a delivery desk and a plurality of stations, means for introduo ing carriers intosaid tubes at said stations, an extended drum for supplying compressed air to said tubes to propel said carriers, said drum extending in adjacency to each of said stations, and means to substantially silently control the exhaust of air from said drum into said tubes, said controlling means'comprising a plurality of co-acting regulating devices, one for each of said tubes, said dc vices being apertured to maintain definitely related normal flows of air through the tubes proportioned to the lengths thereof.

In testimony whereof I have affixed my signature, in the presence of two Witnesses.

ERNEST J. LORING.

ll/itnesses: 7

- lt. Epl ismi,

JAMES l3. Bncirnnr. 

